/*
     * for the sake of this tutorial, we will avoid trapping
     * specific exceptions
     */
    public void simpleConnection()throws Exception
    {
            String path ="http://this/is/your/path/to/the/service";
            java.net.URL url = new java.net.URL(path);
            /* open the connection */
            java.net.HttpURLConnection con = (java.net.HttpURLConnection)url.openConnection();
            /* lets check if the connection was successfully opened */
            if (con.getResponseCode() != java.net.HttpURLConnection.HTTP_OK) {                   
                throw new RuntimeException(
                        "Error calling Search API (HTTP status " + con.getResponseCode() + ")");
            }    
            /* get the incoming data */
            java.io.InputStream stream = con.getInputStream();
    }

Ok so the example above would open a connection and get the input stream, from which we can read the data. now chances are that a lot of the time we would need to call the web service using som e parameters. So how do we do that? well its simple, we simply pass the parameters in the path variable like this

String path ="http://this/is/your/path/to/the/service?param1="+
                java.net.URLEncoder.encode("value1","UTF-8")+
                "&param2="+java.net.URLEncoder.encode("value2","UTF-8");

Now onto the last bit, there is a possibility that your connection may go through a proxy server and in that case the above code sample would throw an error unless we account for the presence of the proxy server. So we accomplish that by letting our program know of the proxy server via System properties.

        java.util.Properties systemProperties = System.getProperties();
        systemProperties.setProperty("http.proxyHost","your-proxy.url.com");
        systemProperties.setProperty("http.proxyPort","1234");

ok so the overall method with the query parameters and the proxy bypass would look something like this

    public void queryWithParamsAndProxy()throws Exception
    {
        java.util.Properties systemProperties = System.getProperties();
        systemProperties.setProperty("http.proxyHost","your-proxy.url.com");
        systemProperties.setProperty("http.proxyPort","1234");

        String path ="http://this/is/your/path/to/the/service?param1="+
                java.net.URLEncoder.encode("value1","UTF-8")+
                "&param2="+java.net.URLEncoder.encode("value2","UTF-8");
      
        java.net.URL url = new java.net.URL(path);
        /* open the connection */
        java.net.HttpURLConnection con = (java.net.HttpURLConnection)url.openConnection();
        /* get the incoming data */
        if (con.getResponseCode() != java.net.HttpURLConnection.HTTP_OK) {                   
            throw new RuntimeException(
                    "Error calling Search API (HTTP status " + con.getResponseCode() + ")");
        }    
        /* get the incoming data */
        java.io.InputStream stream = con.getInputStream();
    }